Re: RE: [COMMITTERS] pgsql/src/backend/access/transam ( xact.c xlog.c)

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> > > > Earlier, Vadim was talking about arranging to share fsyncs of the WAL
> > > > log file across transactions (after writing your commit record to the
> > > > log, sleep a few milliseconds to see if anyone else fsyncs before you
> > > > do; if not, issue the fsync yourself).  That would offer less-than-
> > > > one-fsync-per-transaction performance without giving up any 
> > > > guarantees.
> > > > If people feel a compulsion to have a tunable parameter, let 'em tune
> > > > the length of the pre-fsync sleep ...
> > > 
> > > Already implemented (without ability to tune this parameter - 
> > > xact.c:CommitDelay, - yet). Currently CommitDelay is 5, so
> > > backend sleeps 1/200 sec before checking/forcing log fsync.
> > 
> > But it returns _completed_ to the client before sleeping, right?
> 
> No.

Ewe, so we have this 1/200 second delay for every transaction.  Seems
bad to me.

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